Objective-type dark-field illumination for scattering from microbeads.
We introduce a method for detecting and tracking small particles in a solution near a surface. The method is based on blocking the backreflected illumination beam in an objective-type total internal reflection microscope, leaving unhindered the light scattered by the particles and resulting in dark-...
| Main Authors: | , , , , , |
|---|---|
| 格式: | Journal article |
| 语言: | English |
| 出版: |
2001
|
| 总结: | We introduce a method for detecting and tracking small particles in a solution near a surface. The method is based on blocking the backreflected illumination beam in an objective-type total internal reflection microscope, leaving unhindered the light scattered by the particles and resulting in dark-field illumination. Using this method, we tracked the motion of 60-nm polystyrene beads with a signal-to-noise ratio of 6 and detected 20-nm gold particles with a signal-to-noise ratio of 5. We illustrate the method's use by following the Brownian motion of small beads attached by short DNA tethers to a substrate. |
|---|